The purpose of this study is to assess the elementary school (7th class) students errors concerning the pressure and determine the relationships among these errors. The data was obtained from a test covering all subjects of the pressure unit. This eight-item test was prepared based on the literature. In the data analysis, frequencies and percentage distribution of the errors were determined and relationships among the types of errors were also investigated using hierarchical clustering. The result of the study revealed that the students have conceptual and procedural errors the most. Results also indicate that conceptual errors in different subjects of the pressure unit constitute error categories among themselves, but procedural errors distributed among this conceptual error categories. On the other hand, errors concerning the formulas dont constitute a relationship with the other error categories maintain a different one.
Key words: Science Education, Pressure, Problem Solving, Error Categories